The trade dollar has MASON stamped on the side with the seated lady and an S below the eagle on the back. The colored spots on the gold coin I was told was filler from when someone "cut" bits of the gold from the coin to pay for items.
Gold is close to melt, Trade Dollar is niche and requires someone who has an interest in counterstamped coins. It is lovely though.
The Trade $ has a countermark (from a merchant) on the obverse) te reverse (back) S is the mintmark. The gold piece was formerly jewelry. Worth melt.